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The secret of the skeleton key
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The haunted lighthouse
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The mystery of the pirate's treasure
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Can you crack the code?
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Mysterious messages : a history of codes and ciphers
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Secret messages : concealment, codes, and other types of ingenious communication
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Top secret : a handbook of codes, ciphers, and secret writing
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The secret agent training manual : how to make and break top secret messages
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Enigma :the battle for the code
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The haunted lighthouse
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Geniuses at war : Bletchley Park, Colossus, and the dawn of the digital age
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Beyond the grave
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The mystery of Case D. Luc
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The emperor's code
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In too deep
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Crypto :how the code-rebels beat the government, saving privacy in the digital age
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The code book :how to make it, break it, hack it, crack it
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The enigma girls : how ten teenagers broke ciphers, kept secrets, and helped win World War II
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Pass it on! : all about notes, from secret codes and special inks to fancy folds and dead man's drops
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The case of the double cross
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Trixie Belden and the mysterious code
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King & Kayla and the case of the secret code
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The forbidden island
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Europa
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Pass it on! : all about notes, from secret codes and special inks to fancy folds and dead man's drops
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Navajo code talkers
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Between silk and cyanide : a codemaker's war, 1941-1945
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Solving Zoe
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Cryptonomicon
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The Ultra secret
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Secret messages : concealment, codes, and other types of ingenious communication
-
Mysterious messages : a history of codes and ciphers
-
The secret of the skeleton key
-
Navajo code talkers
-
Crypto :how the code-rebels beat the government, saving privacy in the digital age
-
Enigma :the battle for the code
-
The code book how to make it, break it, hack it, crack it
-
Top secret : a handbook of codes, ciphers, and secret writing
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Code talker : a novel about the Navajo Marines of World War Two
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The Navajo code talkers
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The code book :how to make it, break it, hack it, crack it
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The haunted lighthouse
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The Imitation Game
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The haunted lighthouse
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Code girls : the untold story of the American women code breakers of World War II
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The woman who smashed codes : a true story of love, spies, and the unlikely heroine who outwitted America's enemies
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The secret agent training manual : how to make and break top secret messages
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Secret warriors : the spies, scientists and code breakers of World War I
